Broaching machine



March 1, 1932. L H. BLOOD 1,848,044

BROACHING MACHINE Filed Nov. 13, 1926 3 Sheets-Sheet l Mimi mu-uuumu M51303? I 7/ a, 9 filcmm March 1, 1932. 1.. H. BLOOD BROACHING MACHINE Filed Nov. 13, 1926 5 Sheets-Sheet 2 gwuwntot IIIIIIH athoumq Patented Mar. 1,1932 I UNITED STATES" PATE O LOUIS H. BLOOD, or orivcmnArr, onro, ASSIGNOB 'ro THE cmonmnrr MILLING MACHINE comrm, or cmonma'rr, onro, A CORPORATION or 01110 4 naoncnms macnmn Application filed November 13, 1926. Serial 1V0. 148,125.

This invention relates to improvements in broaching machinery and has particular reference to an improved structure of machine particularly adapted for simultaneous opera- 5 tion upon a multiplicity of articles. One of the principal objects of the present invention is the provision of a broaching machine which shall be substantially automatic in operation and which shall havea minimum I of idle or non-productive'time.

A further object of the invention is the provision of a broaching machine or like machine tool in which the only manual operation necessary shall be the loading of the work 1 pieces, and in whichboth the clamping, cutting, releasing and ejecting of the work shall be automatically performed. 1 Another object of the invention isthe provision of an im roved type of broaching machine adapted or simultaneous operation on a plurality of work pieces which shall occupy a minimum of floor space and provide maximum accessibility for the operator.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification taken in connection with the accompanying drawings, and it will be understood that I may make any modifications in the specific structural details hereinafter disclosed within the scope of the appended claims, without departing from or exceeding the spirit of the invention.

Figure 1 is a plan view of one embodiment 1 of the invention."

Figure 2 is a vertical sectional View on the line 2-2 of Figure 1.

Figure 3 is a view partially in section of a slightly modified form of the invention. Figure 4 is a horizontal section illustrating the compensated double drive for the bull gear.

Figure 5 is a perspective view of a work piece.

Figure 6 is an enlarged vertical section through one of the work-holding fixtures.

Figure 7 is a plan view of a sectional tube cutter, and,

Flgure 8 is a section through the worm 5 drive equalizer.

In the drawings in which similar characters of reference are employed to denote cortion, being a method of cutter lubrication well known in the .art. The basal portion is further formed with a chamber as at 13, overlying a portion of the reservoir and adapted to receive the chips, etc. 14 from the 5 cuttlng. This chamber is separated from the tank 11 by the wall 15 and has an aperture as at 16 closed by a screen grating 17 to permit the commingled coolant to drain back into the tanl; from the chamber, leaving only the dry chips which may be readily removed from the machine as desired through the aperture 18. at the front of the machine. The base is-formed with the apertured top wall 19 which serves as a'support for the remainder of the machine. This wall may have one or more apertures as at 20, covered by screens 21 on which the chips may rest until shifted as hereinafter described to the chamber 13, the coolant in the meantime filtering down through the 'screen as illustrated in Figure 2. Supported by the wall 19 is the main casting of the machine, including the base flange 22 and the outer wall 23, furcated atits upper edge to provide the pair of spaced flanges 24 and 25 which provide a trough 26 to receive any chips or coolant thrown out from the central portion of the machine and prevent same from being diverted into the bearing surfaces. This casting is further on formed with the central cylindrical portion 27 which constitutes the bearing for the ro tary portion of the machine. This rotary portion as shown in Figures 1 and 2 for example, comprises a work carrying table 28 having a depending sleeve 29 journalled on the cylindrical bearing 27 and a basal flange 30 resting on the portion 22 of the main casting of the machine. Surrounding the lower portion of the sleeve and spaced therefrom lot to provide the chamber 31 is the tubular rim 32, chamber 31 serving to contain lubricant 33 which flows inward as through apertures 34 to the oil grooves 35 which thus provide efficient lubrication between cylindrical bearing 27 and sleeve 29, facilitating free relative rotation of said parts.

Toimpart rotation to the table member, use is made of the bull gear 36 driven by one or more worms 37. i I

The table it will be noted is of hollow formation having in its upper face apertures as at 38, through which chips and coolant may fall and be precipitated into the lower part of the main casting as indicated in Figure 2. It is further provided with depending pushers 39 rotating therewith within the main casting 23 to carry around the contained chips to the common discharge aperture 40 leadinginto the chip cooling and draining chamber 13, previously referred to.

Mounted on the upper face of the rotary table member is a plurality of slides 41, whose in and out position may be varied and controlled as by the adjusting screws 42. The structure of the individual units is ordinarily identical and is particularly illustrated in Figure 6. They comprise the main block 43 having the dovetail guide portion 44 and the transverse passage 45, receiving a V block 46 and a clamp block 47, in which is swivelled the lower end of adjusting screw 48. Secured to the upper end of the screw is an actuating bell crank for the arms 49 and 50, each provided with an anti-friction roller 51. The main casting of the machine is provided with an angle bracket 52 having a contact block 53 for cooperation with arm 50, so that as the table rotates in a clockwise direction, considering Figure 1, interengagement of arm 50 and contact 53 will impart a counter-clockwise movement to screw 48, thus lifting block 47 to disengage or release work piece 54, if clamped therein as shown in Figure 6. I

By reference to Figure 1 it will be noted that a blade spring 55 is disposed within the path of the inner ends of the work piece 54, so that as the work piece approaches the spring it will place the spring under tension, tending to rearwardly displace the work piece. This spring pressure increases as the table rotates to release clamping action of screw 48, so that when the screw is released the work piece will be forcibly ejected from the fixture. Bracket 52 serves further as a support for discharge trough 56 disposed in position to receive the individual work pieces as they are successively automatically ejected by spring 55.

The table having progressed beyond this ejecting position, it is then ready to receive a new piece of work which may be longitudinally shoved into the fixture by the operator.

To cause an automatic clamping in position of the work prior to operation thereon by the cutter, there is pivoted to the hereinafter described cutter support 57, the clamp actuating trip arm 58, having a portion 59 extending into the path of movement of arm 49. Therefore, as the table rotates the interengagement of these parts will im art a clockwise movement to screw 48 clamping the new work piece in position. It will be understood that in operation of the rivets for example, such as here illustrated, it is possible there may be slight variations in size or the like rendering it impracticable to employ an absolutely definite amount of rota tion of the screw for clamping purposes on successive work pieces. It is for this reason that the arm 58 is pivotally mounted and held in operative-position as by the spring 60.

This causes it to properly engage arm 49 and impart an amount of turning pressure to the screw which is limited by the tension of spring 60. After the clamp has been tightened this amount the spring will yield, allowing the arm 58 to swing inwardly out of the path of movement of arm 49, thus preventing jamming or possible breakage of parts. The work being thus clamped remains in its clamped condition until movement of the table advances its arm 50 to the actuating abutment 53 for release thereof. The cutter mechanism for operation upon the several progressively shifted work pieces includes a supporting table 57 having slots 61 for T bolts 62 which serve to clamp in osition one or more cutters 63, which may e of either the individual inserted tooth type illustrated in Figure 1, the section tooth type shown in Figure 7 or of other form as desired. Y

In the specific operation illustrated the machine is designed for broaching fiat 64 on the rivet or work piece 54 at diametrically opposite points. For this purpose use is made of two spaced cutter members held in separated position as by the interposed spacing blocks 65, the work being carried around with its end projecting in between the two cutters for proper stock removal therefrom.

It will be apparent from Figures 1 and 7 particularly illustrating the cutter, that the cutter or cutters as employed in this operation are of eccentric form with the result that at the left where the work piece is first brought into engagement with the cutters the extent of the cut axially of the work piece will be but slight, while each succeeding tooth on the cutter will project a minute amount further, outward or in the direction of the work piece, thus eating into the portion to be removed as the table rotates, so that when the work piece reaches the ejecting position at the right front of the table the complete flat 64 will have been formed thereon.

As mentioned the cutter may be either built correspondingly formed so as to be readilyv 1e and are then mounted 1n interchangea sition on the main cutter plate 68, whose seat formation serves to establish their proper location and projection toward the work. If

"desired after assembly, the entire cutter may be ground to produce a smooth continuous arc, the individual sections being slightly deformed by this process and the initial exterior curvature being ordinarily figured asomean' between the curve thus produced on 1 the first and on the final segment, so that the vertical position with respect to the tubular entire cutter may be most easily with a minimum" of final balanced u grinding work on any individual section.

It will be understood that it is necessary to very rigidly and firmly support the cutter and at the same time that itis desirable to have some means of vertical adjustment between the table and its fixtures and the cutter members, in order that the cutters may be most readily positioned to properly operate on one or bot-h sides of the work pieces as desired. To attain this result the cutter supporting table 57 is provided with a depending sleeve 69 fitting within the cylinder 27 of the main casting of the machine and keyed thereto as at 70 to prevent relative rotation of the parts. The table is further formed with a central upstanding boss or projection 71, in which is swivelled the adj usting sleeve 72, threaded into the upper end of the tubular post 73 having a basal flange 7 4 secured to the base 22 of the main cast-- ing. A member 75 on the upperend of sleeve 7 2 facilitates rotation thereof to adjust its post 73. This sleeve is formed with a pcripheral flange 76 carrying the thrust bear- .ing 77 in engagement with the under side of boss 71. As a result, vertical adjustment of the sleeve by rotation thereof also imparts vertical movement to the cutter supporting table 57 as guided by the long bearing therefore provided by its depending sleeve 69. A

ting'uished from the linear movement broaches known to the prior art. It will further be noted that there has been provided a simplified table construction supporting a plurality of individually adjusta le work clamping fixtures, together with means for automatically actuating said fixtures to clamp and unclamp work pieces as the table supthe fixtures is rotated. By such rotarymovement the fixtures are successively presented to an operator standing at the front of the machine who has merely to insert a new work piece in the place of a completed one previously automatically ejected when the continued movement of the table will cause first-a clamping of the work piece and subsequently a proper stock removal therefrom. The entire operation is a continuous one and there is do lost time for feeding or idle return strokes as is the case with the prior reciprocating motion breaching mechanisms. In order that suflicient balanced power may be imparted to the rotary member I prefer to utilize the driving structure particularly illustrated in Figures 4 and 8. Power is applied to the machine through pulley 80 and shaft 81. ,Thence through the change gears 8283, shaft 84 is driven. This shaft has splined or keyed thereon collar 85 formed with an aperture 86 to receive the compensating tumbler pin 87, having a double cone central portion providing a rocking support for the in and having terminal ball ends 88 receive in suitable recesses 89 in the collars 90 and 91. Collar 90 is secured on sleeve 92 which bears miter gear 93 meshing with its mate 94 on shaft 95 of worm 37. Collar 91 is splined or keyed to shaft 96, which through miter gears 9798 drives shaft 99 for a second worm 37 It will'thus be noted that the power drive is transmitted from shaft 84 through the rocking pin 87 to the pair of collars 90 and 91 and this pin by its rocking movement serves to balance up the final drives" 92 and 96, so that the loadisequally distributed and corresponding power suitably applied simultaneously to 0th sides of the worm gear, insuring most satisfactory oper- I vantages in the matter of loading and discharge of the work, it is to be understood that the principle of employment of a circular broach and particularly of a circular broach of eccentric contour, so that proper stock removal is attained during a relative rotary movement of the work and'cutter without a transverse feed during such rotary movement may be otherwise utilized. For ex,- ample, as shown in Figure 3, the work fixtures may be held stationary and the-cutter may be given the rotary movement, its eccentric form causing the progressive stock removal during the relative shifting of the work and cutter.

I claim 1. A machine of the character described, including a bed, a tubular column rising from 4 the bed, a table member rotatably mounted exteriorly on said column, a tubular cutter support slidably but non-rotatably mounted within the column, Work holding fixtures carried by the table, a stationary cutter carried by the cutter support, means for continuously rotating the table to carry Work pieces past the cutter on the support, means mounted interiorly thereof for imparting a vertical sliding 'movement to the support in the column to vary the engagement of the cutter with work pieces carried by the table, said means terminating in an operating member at the top of said cutter support and means coaxial therewith for clamping the support after adjustment.

2. A machine of the character described, including a bed, a tubular column rising from the bed, a table member rotatably mounted exteriorly on said column, a cutter support slidably but non-rotatably mounted within the column, Work holding fixtures carried by the table, a stationary cutter carried by the cutter support, means for rotating the table to carry work pieces past the cutter on the supportand means for imparting a vertical sliding movement to the supvport in the column to vary the engagement of the cutter with the Work pieces carried by the table, said means including an elevating screw and a lock device telescoping the screw for securing the screw and thereby the support in adjusted position..

3. A machine of the character described including a bed, a tubular column rising there from, a table member supported by the bed 1 for rotation about the column, a supporting member slidably but non-rotatably mounted Within the column, a post rising from the bed within the column, an adjusting member-having a shoulder subtending a portion of the support and in threaded engagement with the post whereby rotation of the adjusting member will effect the sliding movement of the support and a clamp member having portions respectively engaging the adjusting member and the bed of the'machine for securing the adjusting member and thus the support in position.

4. A machine of the character described including a bed, a column rising therefrom, having an external bearing portion, a table member rotatably mounted on said bearing portion, work holding fixtures supported by the table and including automatically actuable clamp members, means for rotating the table, a tool carrier having a portion telescoping with the column and an exterior peripheral flange, means for adjusting the tool carrier relative to the column, an interrupted arcuate tool mounted on theperipheral flange substantially in the plane of the work fixtures for operation on the ends of work pieces carried thereby, and a work clamp actuating means on the carrier adjacent the interrupte portions of the tool and a resilient ejector on the carrier projectable into the .path of the work for ejection of the work when the clamping means therefor is released.

5. A machine of the character described including a bed, acolumn rising therefrom having an external bearing portion, a table member rotatably mounted on said bearing portion, work holding fixtures supported by the table and including automatically actuable clamp members, means for continuously rotating the table, a tool carrier having a portion telescoping within the column, means for adjusting the tool carrier relative to the column, an interrupted arcuate tool mounted 011 the tool carrier substantially in the plane of the work fixtures'for operation on the ends of work pieces carried thereby, and a work clamp actuating means on the carrier adjacent the interrupted portions of the tool and in the plane of the work clamp members, said clamp actuating means including a post, a

. cam member pivoted to the post, and means for resiliently urging the cam member into operative position to effect clamping of the Work.

In testimony whereof I afiix my signature.

LOUIS H. BLOOD. 

